Its a solar cell. Photo voltaic Cell is also known as a solar cell.
The work is being done in following cases:
A mover carries a box up a flight of stairs.
A mover carries a box across a room.
Wind blows a pool chair across the yard.
A weightlifter lifts a barbell off the ground.
These are the only cases in which work is being done. The Formula of Work is:
Work= Force applied x Distance moved.
In all of these cases force is being applied and the object on which the force is being applied move in a horizontal or Vertical direction. Thus Work is done !
We have that there is a formula connecting these three. V=I*R where V is voltage, I is the current and R is the resistance. Substituting, we get that V=210 Volta, which is the unit of measurement for voltage. You can think of the relationship in the following way : The energy of the field is equal to the flow of the field times the resistance that it meets.
